Fill(null) not working as expected

Hello Everyone.

I’ve got a query/line graph that isn’t behaving as expected. Where there are no points reported, using the “fill(null)” option should just show empty space. This is not the case. I found several issues on the github page about it, but can’t figure out why it’s not working for me.

If I do bars instead of lines, the space shows up, as shown here: 2017-09-19 10_33_16-Grafana - Networking Stats

If I zoom in close enough, it says: “No data points.”

Here’s what my query looks like:

Any ideas on getting this to display properly with a line graph?

what is your graph display option “null value” set to (find it in the display tab)

It is set to null as well.

maybe something caused by derivative inflxudb func? what if you remove that function?

If I remove the derivative, the gap shows on a line graph, but data is not correct. I’m following this tutorial to gather SNMP data on switches:

The value that is returned is an “octet” format, and thus needs to be derived by 1 second to get the bit/sec value.

ok, then maybe there is a problem with InfluxDB derivative function and fill(null) that is not working correctly.

Is that a bug request I’d need to file with InfluxDB, or grafana?

I found this:

InfluxDB is doing the derivative calculation (and fill(null)) so InfluxDB. You can double check if you run Grafana v4.5 , click Query Inspector , then you can see raw query sent to influxdb and raw response

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I’ll see what I can find, and post if I find a solution/workaround.